I was appalled to be quoted $85 each to replace my two remote key "fobs". My solution was to carefully saw the fob open with a junior hacksaw, following the seam where the two halves had been heat-fused. The battery fitted to the unit is soldered in place and is manufactured with two tabs for the +ve and -ve connections. I bought the batteries (code CR2032-1HFE) from Batteries Direct www.batteriesdirect.com.au for $2.78 each. Unsoldering the old batteries and soldering in the new ones was pretty easy. If you attempt this, just make sure that you use a soldering iron meant for electronics work and not repairing plumbing. The halves were re-assembled and bonded with a good quality silicone adhesive. Both work perfectly. An additional benefit for me was that I replaced the rubber push buttons with silicone buttons from Polmex - www.Polmex.com.au at $15 each. Again, these fitted easily and are working fine. If you can afford Toyota OEM prices, great. Otherwise if, like me, you refuse to be "fobbed off", maybe give the diy approach a shot.
